package simple.array;

import java.util.ArrayList;
import java.util.List;

/**
 * @Desc <a href="https://leetcode.cn/problems/find-common-characters/">1002. 查找共用字符</a>
 * 给你一个字符串数组 words ，请你找出所有在 words 的每个字符串中都出现的共用字符（ 包括重复字符），并以数组形式返回。你可以按 任意顺序 返回答案。
 * 示例 1：
 *   输入：words = ["bella","label","roller"]
 *   输出：["e","l","l"]
 * 示例 2：
 *   输入：words = ["cool","lock","cook"]
 *   输出：["c","o"]
 * 提示：
 *   1 <= words.length <= 100
 *   1 <= words[i].length <= 100
 *   words[i] 由小写英文字母组成
 * @Date 2023/7/2 20:39
 * @Created by 刘学松
 */
public class 查找共用字符 {
    public List<String> commonChars(String[] words) {
        int[] counts = new int[26];
        String word0 = words[0];
        for (int i = 0; i < word0.length(); i++) {
            ++counts[word0.charAt(i)-'a'];
        }
        int length = words.length;
        for (int i = 1; i < length; i++) {
            int[] temp = new int[26];
            String word = words[i];
            for (int j = 0; j < word.length(); j++) {
                ++temp[word.charAt(j)-'a'];
            }

            for (int j = 0; j < 26; j++) {
                counts[j] = Math.min(counts[j], temp[j]);
            }
        }
        List<String> list = new ArrayList<>();
        for (int i = 0; i < 26; i++) {
            if (counts[i] > 0) {
                char c = (char)(i+'a');
                for (int j = 0; j < counts[i]; j++) {
                    list.add(String.valueOf(c));
                }
            }
        }
        return list;
    }
}
